Perfusion system with rfid

ABSTRACT

The disclosure pertains to a perfusion system that is easy to set-up, use and monitor during a bypass procedure. In some embodiments, the disclosure pertains to a perfusion system in which at least some of the disposable components used with the perfusion system are configured to be able to communicate set-up and/or operational parameters to the perfusion system. In some embodiments, the disclosure pertains to a blood level sensor that can be used to monitor a blood level or volume within a blood reservoir. The blood level sensor may be utilized in an integrated perfusion system in which the disposable components are configured, as noted above, to communicate with the perfusion system. In some embodiments, the blood level sensor may be utilized with a perfusion system lacking communication with disposables.

TECHNICAL FIELD

The disclosure pertains generally to perfusion systems and moreparticularly to integrated perfusion systems configured to communicatecomponent-specific information between system components.

BACKGROUND

Perfusion entails encouraging physiological solutions such as bloodthrough the vessels of the body or a portion of a body of a human oranimal. Illustrative examples of situations that may employ perfusioninclude extracorporeal circulation during cardiopulmonary bypass surgeryas well as other surgeries. In some instances, perfusion may be usefulin providing extracorporeal circulation during various therapeutictreatments. Perfusion may be useful in maintaining the viability of bodyparts such as specific organs or limbs, either while the particular bodypart remains within the body, or while the body part is exterior to thebody such as for transplantation or if the body part has beentemporarily removed to provide access to other body structures. In someinstances, perfusion may be used for a short period of time, typicallydefined as less than about six hours. In some cases, perfusion may beuseful for extended periods of time that are greater than about sixhours.

In some instances, blood perfusion systems include one or more pumps inan extracorporeal circuit that is interconnected with the vascularsystem of a patient. Cardiopulmonary bypass (CPB) surgery typicallyrequires a perfusion system that allows for the temporary cessation ofthe heart by replacing the function of the heart and lungs. This createsa still operating field and allows for the surgical correction ofvascular stenosis, valvular disorders, and congenital heart and greatvessel defects. In perfusion systems used for cardiopulmonary bypasssurgery, an extracorporeal blood circuit is established that includes atleast one pump and an oxygenation device to replace the functions of theheart and lungs.

More specifically, in cardiopulmonary bypass procedures, oxygen-poorblood (i.e., venous blood) is gravity-drained or vacuum suctioned from alarge vein entering the heart or other veins (e.g., femoral) in the bodyand is transferred through a venous line in the extracorporeal circuit.The venous blood is pumped to an oxygenator that provides for oxygentransfer to the blood. Oxygen may be introduced into the blood bytransfer across a membrane or, less frequently, by bubbling oxygenthrough the blood. Concurrently, carbon dioxide is removed across themembrane. The oxygenated blood is then returned through an arterial lineto the aorta, femoral, or other main artery.

A perfusion system typically includes various fluid circuitry andcomponents that are configured by medical personnel prior to the bypassprocedure. This can be a time consuming process and may requiresignificant manual input of information relating to various componentsof the system.

SUMMARY

According to an embodiment of the present invention, an integratedperfusion system includes a heart lung machine and one or moredisposable elements that are configured to be used in conjunction withthe heart lung machine. The heart lung machine includes a plurality ofpump modules, each of which has a control unit. The heart lung machinealso includes a controller that is in communication with each of thepump module control units, an input device that is in communication withthe controller and that is configured to accept operational settingsinformation from a user and an output device that is in communicationwith the controller and that is configured to display operationalparameters of the plurality of pump modules. The heart lung machine alsoincludes an RF sensor that is in communication with the controller. Theone or more disposable elements include an RFID tag that is programmedwith disposable element-specific information that can be read by the RFsensor and used by the controller to regulate operation of the heartlung machine in place of at least some operational parameters otherwiseinputted by the user.

According to another embodiment of the present invention, a method ofconfiguring an integrated perfusion system having a heart lung machinewith an RF sensor and a disposable component with an RFID tag includesattaching the disposable component having an RFID tag to the heart lungmachine. The RFID tag is read with the RF sensor, and operation of theheart lung machine is configured based at least in part upon informationprovided from the RFID tag to the RF sensor.

According to another embodiment of the present invention, a heart lungmachine pack includes a housing configured to hold a plurality ofdisposable elements for a heart lung machine, a tubing set and acomponent. The tubing set includes a first RFID tag secured to thetubing set and is configured for one-time use with a heart lung machine.The component has a second RFID tag secured to the component and isconfigured for one-time use with a heart lung machine.

While multiple embodiments are disclosed, still other embodiments of thepresent invention will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of an integrated perfusion system inaccordance with an embodiment of the invention.

FIG. 2 is a flow diagram illustrating a method that can be carried outby the integrated perfusion system of FIG. 1.

FIG. 3 is a flow diagram illustrating a method that can be carried outby the integrated perfusion system of FIG. 1.

FIG. 4 is a schematic illustration of a heart lung machine pack that maybe utilized with the integrated perfusion system of FIG. 1.

FIG. 5 is a schematic illustration of a perfusion system in accordancewith an embodiment of the invention.

FIG. 6 is an illustration of a blood level sensor that may be utilizedwith the perfusion system of FIG. 5.

FIG. 7 is an illustration of a blood level sensor incorporated into alabel that may be utilized with the perfusion system of FIG. 5.

FIG. 8 is an illustration of a blood reservoir including a blood levelsensor in accordance with an embodiment of the invention.

FIG. 9 is an illustration of a hard shell blood reservoir including ablood level sensor in accordance with an embodiment of the invention.

FIG. 10 is an illustration of a soft shell blood reservoir including ablood level sensor in accordance with an embodiment of the invention.

FIG. 11 is a flow diagram illustrating a method that can be carried outusing the perfusion system of FIG. 5.

FIG. 12 is an illustration of a blood reservoir including a blood levelsensor in accordance with an embodiment of the invention.

FIG. 13 is an illustration of a blood reservoir including a blood levelsensor in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

The disclosure pertains to a perfusion system that is easy to set-up,use and monitor during a bypass procedure. In some embodiments, thedisclosure pertains to a perfusion system in which at least some of thedisposable components used with the perfusion system are encoded withset-up and/or operational parameters. In some embodiments, thedisclosure pertains to a blood level sensor that can be used to monitora blood level or volume within a blood reservoir. The blood level sensormay be utilized in an integrated perfusion system in which thedisposable components are configured, as noted above, to communicatewith the perfusion system. In some embodiments, the blood level sensormay be utilized with a perfusion system lacking communication withdisposables.

FIG. 1 is a schematic illustration of an integrated perfusion system 10including a heart lung machine (HLM) 12 and a disposable element 14.While only a single disposable element 14 is shown for ease ofillustration, in many embodiments a plurality of different disposableelements 14 may be utilized in combination with the HLM 12. Each of theHLM 12 and the disposable element 14 will be described in greater detailsubsequently. The HLM 12 includes a number of different components. Itis to be understood that the particular components illustrated herein asbeing part of the HLM 12 is merely an example, as the HLM 12 may includeother components or different numbers of components.

In the illustrated embodiment, the HLM 12 includes three pump modules16, but may include as few as two pump modules 16 or as many as six orseven pump modules 16. In some embodiments, the pump modules 16 may beroller or peristaltic pumps. In some embodiments, one or more of thepump modules 16 may be centrifugal pumps. Each of the pump modules 16may be used to provide fluid or gas for delivery to or removal from theheart chambers and/or surgical field. In an illustrative butnon-limiting example, one pump module 16 draws blood from the heart,another provides surgical suction and a third provides cardioplegiafluid (high potassium solution to arrest the heart). Additional pumpmodules 16 (not shown) may be added to provide additional fluidtransfer.

Each pump module 16 includes a control unit 18. In some embodiments,each control unit 18 may be configured to operate and monitor theoperation of the particular pump module 16 to which it is attached orotherwise connected to. In some embodiments, each control unit 18 mayinclude one or more input devices (not illustrated) such as switches,knobs, buttons, touch screens and the like so that the perfusionist mayadjust the operation of the particular pump module 16. Each pump module16 may include an alphanumeric display that the control unit 18 can useto display, for example, the value of a setting, the value of a currentoperating parameter, confirmation that the pump module 16 is operatingnormally, and the like.

The HLM 12 includes a controller 20 that is in communication with thecontrol units 18 and that is configured to operate the HLM 12. In someembodiments, the controller 20 is configured to monitor one or moresensors that may be distributed on the HLM 12 and/or within thedisposable element 14 to monitor operation of the HLM 12. Examples ofsuch sensors (not illustrated for ease of illustration) include but arenot limited to flow meters, pressure sensors, temperature sensors, bloodgas analyzers and the like.

While the control units 18 and the controller 20 are illustrated asdistinct elements, in some embodiments it is contemplated that theseelements may be combined in a single controller. In some embodiments, itis contemplated that the control units 18, in combination, may beconfigured to operate the HLM 12, thereby negating a need for thecontroller 20.

The controller 20 communicates with an input device 22 and an outputdevice 24. The input device 22 may be used by the perfusionist to enterinformation that is not otherwise entered into the control units 18. Theoutput device 24 may be used by the HLM 12 to display pertinentinformation to the perfusionist. In some embodiments, the input device22 may be a key pad, a keyboard, a touch screen, and the like. In someembodiments, the output device 24 may be a monitor. In some embodiments,either of the input device 22 and/or the output device 24 may be acomputer such as a personal computer, a laptop computer, a notebookcomputer or a tablet computer. In some cases, the input device 22 andthe output device 24 may be manifested in a single computer.

The HLM 12 also includes an RF sensor 26. In some embodiments, the RFsensor 26 may be configured to receive information from an active RFIDtag placed on the disposable element 14. In some embodiments, the RFsensor 26 may be a hand held device that is used to scan a passive RFIDtag on the disposable element 14. According to other embodiments, the RFsensor 26 is replaced with any of a variety of known wirelesscommunication receivers. The disposable element 14 includes an RFID tag28. According to various embodiments, the disposable element 14 includeseither an active RFID tag or a passive RFID tag (or both) configured tocommunicate with the RF sensor 26. In other embodiments, the RFID tag 28is replaced with any of a variety of known wireless communicationtransmitters.

Passive RFID tags lack a power supply, and instead are powered by aninduced current caused by an incoming radio-frequency scan. Becausethere is no onboard power supply, a passive RFID tag is smaller and lessexpensive. An active RFID tag includes an onboard power supply such as abattery. While this increases the size and expense of the RFID tag, anadvantage is that the RFID tag can store more information and cantransmit further. RFID tags, whether active or passive, may be selectedto transmit at a variety of frequencies depending on need. Optionsinclude low frequency (about 100 to 500 kilohertz), high frequency(about 10 to 15 megahertz), ultra high frequency (about 860 to 960megahertz) and microwave (about 2.45 gigahertz).

As noted above, the disposable element 14 may be considered asgenerically representing one, two or a plurality of different disposableelements that may be used in conjunction with the HLM 12. Illustrativebut non-limiting examples of disposable elements 14 include tubing sets,blood reservoirs, oxygenators, heat exchangers and arterial filters. Insome embodiments, a tubing set includes a number of different tubes,potentially of different lengths and sizes, for providing fluid flowbetween components of the HLM 12 as well as providing fluid flow betweenthe HLM 12 and a patient.

In some embodiments, the disposable element 14 may be a blood reservoirsuch as a venous blood reservoir, a vent blood reservoir, a cardiotomyor suction blood reservoir. In some embodiments, the disposable element14 may be a blood reservoir that combines one or more of a venous bloodreservoir, a vent reservoir and/or a suction reservoir in a singlestructure. In some embodiments, one or more of the aforementionedsensors may be disposable elements that include an RFID tag 28 either toprovide information identifying the sensor or even for transmittingsensed values to the controller 20.

The RFID tag 28 may be attached to the disposable element 14 in anyappropriate manner. In some embodiments, the RFID tag 28 may beadhesively secured to the disposable element 14. In some embodiments,the RFID tag 28 may be molded into the disposable element 14. In someembodiments, the RFID tag 28 may be a stand alone card, similar in sizeand shape to a credit card, that may simply be packed with thedisposable element 14 in such a way that it can be removed by the userand swiped by the RF sensor 26. However the RFID tag 28 is attached, theRFID tag 28 may be programmed with or otherwise configured to include awide variety of information pertaining to the disposable element 14.

In some embodiments, the RFID tag 28 may include data or identifyinginformation for the disposable element 14. Illustrative but non-limitingexamples of identifying information include the name of the particulardisposable element 14, a reference code, a serial number, a lot number,an expiration date and the like. In some embodiments, this informationmay be communicated to the controller 20 and may, for example, be usedby the controller 20 to confirm that the proper disposable elements 14are being used for a particular setting, patient or the like. As anexample, the controller 20 may recognize that a pediatric tubing set isbeing used in combination with an adult-sized blood reservoir or othercomponent. As another example, the controller 20 may recognize that anexpected component is missing. There are a variety of other potentialmismatches in equipment that may be recognized by the controller 20 as aresult of the information provided by the RFID tag 28 attached to eachof the one or more disposable elements 14.

In some embodiments, the RFID tag 28 may include descriptive or designinformation for the disposable element 14. Illustrative but non-limitingexamples of descriptive or design information include specificmaterials, a list of components, priming volume of a component or tubingcircuit, tubing size, tubing length, minimum and maximum workingpressures, minimum and maximum working volume, and the like. In someembodiments, this information may be communicated to the controller 20and may be used by the controller 20 to at least partially configureand/or operate the HLM 12. As an example, the controller 20 may use thesizing information provided from each of the disposable elements 14 todetermine a working blood volume for the HLM 12.

In some embodiments, the information obtained from the RFID tag 28 mayalso be provided to the perfusionist. In some embodiments, the outputdevice 24 may be configured to provide alphanumeric or graphicalrepresentations of the obtained information. In some cases, the RFID tag28 may include instructional information that may be displayed by theoutput device 24 in order to instruct the perfusionist in optimal setupand/or operation of a particular disposable element 14. In variousembodiments, the output device 24 may be a computer such as a personalcomputer, a laptop computer, a notebook computer or a tablet computer.In some embodiments, the RFID tag 28 may include displayable informationthat, for example, suggests an optimal circuit design based upon thespecific components being used, or perhaps updated use instructions. Insome embodiments, information from the RFID tag 28 is displayed on anintegrated data management system (DMS).

In some embodiments, the RFID tag 28 may include information that amanufacturer of the disposable element 14 wants to provide to the user.Examples of such information may include technical features of thedisposable element 14 that have changed from a previous version or evena previous batch. Another example includes information that can bedisplayed by the output device 24 that require the user to acknowledgereceipt of the information before the controller 20 proceeds with aparticular procedure. In some cases, the RFID tag 28 may receive errormessages from the controller 20, and the RFID tag 28 may then bereturned to the manufacturer, thereby providing the manufacturer withfeedback regarding the performance of the disposable element 14 as wellas other components.

FIG. 2 is a flow diagram illustrating a method that may be carried outusing the perfusion system 10 of FIG. 1. A disposable element 14 havingan RFID tag 28 may be attached to the HLM 12, as generally shown atblock 30. At block 32, the RFID tag 28 is read. As noted above, the RFIDtag 28 may be an active RFID tag or a passive RFID tag. In someembodiments, the RFID tag 28 may be read before the disposable element14 is attached to the HLM 12. In some embodiments, the RFID tag 28 maybe read after attachment. At block 34, the HLM 12 is configured based atleast in part upon information that was read from the RFID tag 28 atblock 32. In some embodiments, the controller 20 automaticallyconfigures the HLM 12 in response to this information.

FIG. 3 is a flow diagram illustrating a method that may be carried outusing the perfusion system 10 of FIG. 1. A disposable element 14 havingan RFID tag 28 may be attached to the HLM 12, as generally shown atblock 30. At block 32, the RFID tag 28 is read. The RFID tag 28 may beread either before or after the disposable element 14 is attached to theHLM 12. At block 34, the HLM 12 is configured based at least in partupon information that was read from the RFID tag 28 at block 32. In someembodiments, the controller 20 automatically configures the HLM 12 inresponse to this information. At least some of the information read fromthe RFID tag 28 may be displayed on the output device 24, as seen atblock 36.

FIG. 4 is a schematic illustration of a heart lung machine pack 38 thatmay be utilized with the perfusion system 10 of FIG. 1. In someembodiments, the heart lung machine pack 38 may include all of thedisposable elements 14 that will be used together for a particularpatient and may be customized for the particular patient. In someembodiments, the heart lung machine pack 38 may include a housing 40that, once filled, can be sealed up to keep the contents clean andsterile

In the illustrated embodiment, the heart lung machine pack 38 includes atubing set 42 and a disposable component 44. The tubing set 42 mayinclude a plurality of different tubes. The disposable component 44 maybe any of the disposable components discussed above with respect to thedisposable element 14. In some embodiments, the heart lung machine pack38 will include a plurality of different disposable components 44. Thetubing set 42 includes a first RFID tag 46 while the disposablecomponent 44 includes a second RFID tag 48. As discussed above, each ofthe first RFID tag 46 and the second RFID tag 48 may be either active orpassive RFID tags and may include readable information pertaining to thecomponent to which they are attached. In some instances, the housing 40may include a third RFID tag 50 that, for example, identifies thecontents of the heart lung machine pack 38. In some embodiments, thefirst RFID tag 46 and the second RFID tag 48 may not be included, as thethird RFID tag 50 may be encoded with all of the information for thetubing set 42 and the disposable component 44.

FIG. 5 is a schematic illustration of a perfusion system 52. Theperfusion system 52 includes an HLM 54 that in some embodiments may besimilar in structure and operation to the HLM 12 discussed with respectto FIG. 1. The perfusion system 52 also includes a blood reservoir 56, ablood level sensor 58 and a controller 60. The blood reservoir 56 may bea venous blood reservoir, a vent blood reservoir, a cardiotomy orsuction blood reservoir. In some embodiments, the blood reservoir 56 maybe a blood reservoir that combines one or more of a venous bloodreservoir, a vent reservoir and/or a suction reservoir in a singlestructure.

The blood level sensor 58 may be configured to continuously monitor avariable blood level within the blood reservoir 56. The blood levelsensor may be chosen from a variety of different sensing technologies.In some embodiments, as will be discussed subsequently with respect toFIGS. 12 and 13, the blood level sensor 58 may be an ultrasonic sensorin which ultrasound is used to detect the blood level within the bloodreservoir 56. In some embodiments, the blood level sensor 58 may be anoptical sensor in which a laser beam or light from an infrared lightsource is reflected by the liquid-air interface and the reflected lightbeam is detected by the blood level sensor 58. According to exemplaryembodiments, the blood level sensor 58 is an optical distance sensor ofthe type commercially sold by Leuze electronic GmbH located inOwen/Teck, Germany (e.g., ODSL8, ODSL 30, or ODS 96). In someembodiments, the blood level sensor 58 may be a load cell or scale thatis configured to measure a mass of the blood reservoir 56 and therebydetermine the volume of blood therein.

In some embodiments, the blood level sensor 58 may be a capacitivesensor (better illustrated in subsequent Figures) that outputs anelectrical signal that is proportional to or otherwise related to ablood level within the blood reservoir 56. The electrical signal may becommunicated in either a wired or wireless fashion to the controller 60.While the controller 60 is shown as a distinct element, in someembodiments the controller 60 is manifested as part of a controller(similar to the controller 20) operating the HLM 54.

In some embodiments, the blood level sensor 58 may be modeled aftercapacitive sensors (e.g., CLC or CLW series) available commercially fromSensortechnics GmbH located in Puchheim, Germany, which are configuredto provide contact-free measurement of continuous liquid level. Thesensor available from Sensortechnics may be disposed on an outer surfaceof a container and provides an electrical signal representative of theliquid level within the container. In some instances, the Sensortechnicssensor may be spaced as much as about five millimeters from the liquidwithin the sensor, with no more than about twenty percent air gapbetween the sensor and the liquid. According to various embodiments, thecapacitive sensor 58 is molded inside the blood reservoir 56, such thatonly the connector is accessible outside the reservoir. In theseembodiments, the sensor 58 is protected by the plastic material of theblood reservoir.

In some embodiments, the sensor may undergo an initial configuration toadapt the sensor to the particulars of the container itself as well asthe liquid within the container. In some embodiments, the blood levelsensor 58 has a five pin electrical connection, including a voltagesource, an analog signal out, a digital signal out, a teach-in pin and aground. In some embodiments, the level sensor 58 is a capacitive sensorsuch as the Balluff SmartLevel sensor commercially sold by Balluff GmbHlocated in Neuhausen, Germany.

The controller 60 may receive an electrical signal that is proportionalto or at least related to a blood level within the blood reservoir 56.The controller 60 may calculate a blood volume based on this electricalsignal as well as a known shape or geometry of the blood reservoir 56.In some embodiments, the blood reservoir 56 may include an RFID tag (notillustrated) that provides the controller 60 with information pertainingto the known geometry of the blood reservoir 56.

If the blood reservoir 56 is a hard shell blood reservoir, the knowngeometry of the blood reservoir 56 may include the cross-sectional areaof the blood reservoir 56, or a width and depth of the blood reservoir56 as well as details on how this cross-sectional area varies relativeto height within the blood reservoir 56. If the blood reservoir 56 is asoft shell reservoir, the known geometry may be based at least in partupon a known lateral expansion rate of the soft shell reservoir relativeto the blood level within the blood reservoir 56.

As can be seen in FIG. 6, the blood level sensor 58 includes a firstelongate electrode 60 and a second elongate electrode 62. The firstelongate electrode 60 and the second elongate electrode 62 are disposedalong a flexible substrate 64. In some embodiments, the flexiblesubstrate 64 may include an adhesive layer that can be used to securethe blood level sensor 58 to the blood reservoir 56. A connector socket66 is secured to the flexible substrate 64 and is electrically connectedto the first elongate electrode 60 and the second elongate electrode 62in order to permit an electrical connection between the first and secondelectrodes 60, 62 and an electrical cable (not illustrated in thisFigure). In some embodiments, rather than an elongate sensor, the bloodlevel sensor 58 may include two or more distinct SMARTLEVEL™ capacitivesensors such as those available commercially from Balluff. These sensorsmay provide a binary, yes/no signal. By locating several of thesesensors at differing levels proximate the blood reservoir 56, the bloodlevel within the blood reservoir 56 may be determined.

In some embodiments, the blood level sensor 58 may be attached to orotherwise integrated into a label 68 as seen in FIG. 7. The label 68 mayinclude various indicia 70 such as use instructions, volume indicatorsand the like. In some embodiments, the label 68 may include an adhesiveside for attachment to an outer surface of the blood reservoir 56. Insome embodiments, the label 68 is oriented on the blood reservoir suchthat a lower portion of the blood level sensor 58 is aligned at or neara bottom of the blood reservoir 56.

In some embodiments, the blood level sensor may be an ultrasonic bloodlevel sensor, as illustrated in FIGS. 12 and 13. FIG. 12 is anillustration of a blood reservoir 82 that contains a volume of blood.The volume of blood defines an interface 84 between the volume of bloodand the air or other fluid within the blood reservoir 82. In someembodiments, an ultrasonic transducer 86 that is located at or near alower surface of the blood reservoir 82 can be used to locate theinterface 84 by transmitting ultrasonic waves 88 towards the interface84. The reflectance of the ultrasonic waves 88 depend at least in partupon the fluid they are passing through. Thus, by measuring thereflectance, the ultrasonic transducer 86 can determine how far away theinterface 84 is and thereby determine the fluid level. Based on thefluid level and the geometric configuration of the blood reservoir 82, acontroller may determine the blood volume within the blood reservoir 82.In some embodiments, a cable 90 transmits a signal from the ultrasonictransducer 86 to the controller. In some embodiments, the information istransmitted wirelessly, such as via an RFID tag attached to theultrasonic transducer.

FIG. 13 is similar to FIG. 12, but shows a blood reservoir 92 having ablood volume defining an interface 94. In this embodiment, an ultrasonictransducer 96 is located at or near a top of the blood reservoir 92 andtransmits ultrasonic waves 98 downward towards the interface 94. In someembodiments, a cable 100 transmits a signal from the ultrasonictransducer 96 while in other embodiments this is done wirelessly, suchas with an RFID tag attached to the ultrasonic transducer 96. A primarydifference between the embodiments shown in FIGS. 12 and 13 is that inFIG. 12, the interface 84 is detected from below, or through the blood,while in FIG. 13 the interface 94 is detected from above.

In some embodiments, the blood level sensor may be an infrared (IR)light blood level sensor. In some embodiments, an infrared light sourcepositioned at or near a lower surface of the blood reservoir 82 may beused to locate a fluid/air interface within the blood reservoir 82 bytransmitting infrared light towards the interface. Alternatively, theinfrared light blood level sensor may be located above the interface. Insome embodiments, the infrared light blood level sensor may be located ashort distance away from the blood reservoir 82 and thus can be attachedto a mechanical holder for the blood level reservoir 82.

In some instances, the infrared light is reflected back towards theinfrared light blood level sensor. By measuring the reflectance, thelocation of the interface may be determined. In some embodiments, theinfrared light travels through the blood to an infrared light sensorlocated opposite the infrared light blood level sensor. By detectingchanges in the received light, the interface location may be determined.By combining the interface location with known geometric parameters ofthe blood reservoir 82, the controller 20 can determine the blood volumewithin the blood reservoir 82. In some embodiments, this information istransmitted wirelessly to the controller 20, such as via an RFID tagattached to the infrared light blood level sensor.

FIG. 8 is an illustration of the blood level sensor 58 attached to theblood reservoir 56. An electrical cable 72 provides an electricalconnection between the blood level sensor 58 and the controller 60. Theelectrical cable 72 includes a plug 73 that is configured to connect tothe electrical connector 66. In some embodiments, the plug 73 includescircuitry that converts a detected capacitance into a voltage signalthat the controller 60 can use to calculate the blood volume. In someembodiments, the plug 73 further includes circuitry to calculate theblood volume.

As noted above, the blood reservoir 56 may be either a hard shellreservoir or a soft shell reservoir. FIG. 9 illustrates a hard shellreservoir 74 bearing the blood level sensor 58 while FIG. 10 illustratesa soft shell reservoir 76 including the blood level sensor 58. In eithercase, the reservoir may be constructed to include the blood level sensor58. In some embodiments, the blood level sensor 58 may be adhesivelysecured to an existing blood reservoir.

FIG. 11 is a flow diagram illustrating a method that may be carried outusing the perfusion system 52 of FIG. 5. A capacitance between first andsecond electrodes may be detected, as referenced at block 78. In someembodiments, as discussed above, the capacitance may be converted intoan electrical signal representing the blood level by circuitry withinthe plug 73. In embodiments using the CLC series Sensortechnics sensor,for example, the sensor will output a voltage between 0.5 and 4.5 volts.Assuming the sensor pad is appropriately located on the reservoir, thisvoltage indicates a level or height of the liquid in the reservoir. Atblock 80, the controller 60 may calculate a blood volume that is basedupon the detected capacitance and a known dimensions or geometry of theblood reservoir 56. In some embodiments, the controller 60 (or othercircuitry within the HLM 54) may provide the circuitry in the plug 73with sufficient information (e.g., dimensions or geometry) regarding theblood reservoir 56 to permit the circuitry to perform the blood volumecalculation. In some embodiments, the calculated blood volume iscommunicated to the HLM 54 so that it may adjust an operating parameterof the HLM 54. In various exemplary embodiments, the HLM 54 may alter apump speed to either increase or decrease blood flow into or out of theblood reservoir 56. It may be important, for example, to prevent theblood level in the reservoir 56 from moving below a certain minimumlevel or volume. Accordingly, in various embodiments, the HLM willcompare the blood level or volume to this minimum level and adjust pumpspeed appropriately.

According to other embodiments, the HLM may use the blood volumeinformation for a variety of applications, including for exampleauto-regulation of pump occlusion, auto-loading of pump segments,conducting automatic occlusivity testing, performing automatic priming,automatic recirculating and debubbling, conducting automatic pressuretests, or performing automatic system emptying.

Various modifications and additions can be made to the exemplaryembodiments discussed without departing from the scope of the presentinvention. For example, while the embodiments described above refer toparticular features, the scope of this invention also includesembodiments having different combinations of features and embodimentsthat do not include all of the above described features.

1. AN integrated perfusion system comprising: a heart lung machineincluding a plurality of pump modules, each pump module including acontrol unit; a controller in communication with each of the pump modulecontrol units; an input device in communication with the controller andconfigured to accept operational settings information from a user; anoutput device in communication with the controller and configured todisplay operational parameters of the plurality of pump modules; and anRF sensor in communication with the controller; and one or moredisposable elements configured to be used in conjunction with the heartlung machine and including an RFID tag programmed with disposableelement-specific information that can be read by the RF sensor and usedby the controller to regulate operation of the heart lung machine inplace of at least some operational parameters otherwise inputted by theuser.
 2. The integrated perfusion system of claim 1, wherein the one ormore disposable elements include tubing.
 3. The integrated perfusionsystem of claim 1, wherein the one or more disposable elements includeone or more of a blood reservoir, an oxygenator, a heat exchanger, or anarterial filter.
 4. The integrated perfusion system of claim 3, whereinthe blood reservoir comprises a venous blood reservoir, a suction bloodreservoir, a vent blood reservoir or a combination thereof.
 5. Theintegrated perfusion system of claim 1, wherein the disposable-specificinformation comprises identifying information.
 6. The integratedperfusion system of claim 1, wherein the disposable-specific informationcomprises performance parameters.
 7. The integrated perfusion system ofclaim 1, wherein the one or more disposable elements include a passiveRFID tag.
 8. The integrated perfusion system of claim 1, wherein the RFsensor comprises a hand-held RD reader.
 9. The integrated perfusionsystem of claim 1, wherein the input device comprises a touch screencomputer.
 10. A method of configuring an integrated perfusion systemincluding a heart lung machine having an RF sensor and a disposablecomponent having an RFID tag, the method comprising steps of: attachingthe disposable component having an RFID tag to the heart lung machine;reading the RFID tag with the RF sensor; and configuring operation ofthe heart lung machine based at least in part upon information providedfrom the RFID tag to the RF sensor.
 11. The method of claim 10, whereinreading the RFID tag with the RF sensor comprises scanning a passiveRFID tag with an RF reader.
 12. The method of claim 10, whereinconfiguring operation of the heart lung machine comprises providing acontroller with the information provided from the RFID tag to the RFsensor.
 13. The method of claim 10, further comprising displayinginformation provided from the RFID tag to the RF sensor.
 14. The methodof claim 10, wherein attaching the disposable component having an RFIDtag to the heart lung machine precedes reading the RFID tag with the RFsensor.
 15. A heart lung machine pack comprising: a housing configuredto hold a plurality of disposable elements for a heart lung machine; atubing set having a first RFID tag secured to the tubing set, the tubingset configured for one-time use with a heart lung machine; and acomponent having a second RFID tag secured to the component, thecomponent configured for one-time use with a heart lung machine.
 16. Theheart lung machine pack of claim 15, wherein the component having anRFID tag secured thereto includes one or more of a venous bloodreservoir, a suction blood reservoir, a vent blood reservoir, a combinedblood reservoir, an oxygenator, a heat exchanger or an arterial filter.17. The heart lung machine pack of claim 15, wherein the first RFID tagincludes readable information relating to volumetric parameters of thetubing set.
 18. The heart lung machine pack of claim 15, wherein thesecond RFID tag includes readable information relating to performanceparameters of the component.
 19. The heart lung machine pack of claim15, wherein the first RFID tag and the second RFID tag each comprise apassive RFID tag.
 20. The heart lung machine pack of claim 15, whereinthe housing includes a third RFID tag that includes readable informationidentifying the contents of the heart lung machine pack.